Each time a "Spellbook" Spell Card is activated, place 1 Spell Counter on this card. All Spellcaster-Type monsters you control gain 100 ATK for each Spell Counter on this card. When this card with Spell Counter is destroyed and sent to the Graveyard: You can add 1 Spellcaster-Type monster from your Deck to your hand, whose Level is less than or equal to the number of Spell Counter(s) that were on this card.